Can't help with the actual question, but do you actually need ethernet connections? Have you considered a mesh? Something like:
www.amazon.co.uk/TP-Link-Dual-Band-Cove ... 0B644N72G/I've got a TP Link system, primary router on the middle floor with physically connected unit, then another unit on top floor & ground floor, which gives a steady speed throughout the house. Obviously, ethernet is going to be best, but for the amount of work, cost etcetera, a mesh may be a better way forwards? Another alternative would be powerline adaptors?
www.amazon.co.uk/TP-Link-Dual-Band-Cove ... 0B644N72G/Not recommending those specific products, my mesh is a few years old now, so not sure what is best now, but as a starting point, if not already considered.